Apparatus sensitive to atmospheric conditions



v April4, 1939. A. T. MATTHEWS ET AL 3,

APPARATUS SENSITIVE TO ATMOSPHERIC CONDITIONS Filed Jan. es, 1936 E'- Caddsn J/bEEZ T-mailhews [hEE/EE Patented Apr. 4.1939

PATENT 'TOFFICE UNITED STATES APPARATUS snnsmvn 'ro ATMOSPHERIC CONDITIONS.

Albert T. Matthews, Thomaston,-Ga., and Charles C. Caddem-Akron, Ohio, assignors to The B. F. Goodrich Company, New York, N. Y., a corporation of New York Application January 6, 1936, Serial No.',57,698

3 Claims. (Cl. 2971) This invention relates to apparatus sensitive to atmospheric conditions and more especially to apparatus sensitive to both the temperature and used to control humidifying apparatus. Suchdevices however have been ineflicient in opera. tion due to the fact that at least they have only approximately determined the relative humidity of the air and have not been responsive to'.temperature change, and over the range of temperatures experienced in the hottest weather the hygros'copic material used as the sensitive element of the-device has not been responsive to slight changes of humidity.- a 5 The present invention aims to provide apparatus wherein a plurality of elements, one of which is sensitive to moisture, and another ofwhich is sensitive to temperature changes, are so com- Joined as more effectively to indicate the atmos-- pheric condition or to control such condition.

The principal objects of the invention are to provide efficiency,

apparatus.

Other objects will appear from the following 7 description and the accompanying drawing.

Of the drawing: Fig. 1 is a front elevation of the preferred form of apparatus showing it as used to control the humidity of the air, parts being broken away.

line 2-2 of Fig. 1. a

Fig. 3 is a rear elevation'of the same. Referring to the drawing, the device in its preferred form includes a stationary frame comprising a pair of rods l0, l fixed in parallel spaced a pair of spacer bars l2 and I3. A similarly disposed pair of rods l4, M, are fixed to a cross head I5 and are slideably mounted in apertures formed in bars [2 and I 3. An arm I6 is pivotedat its center on a screw l1 having threaded engagement with spacer bar l2, the arrangement being such that when the screw I1 is loosened slightly the arm l6 may be turned. thereon as a pivot but when the screw. is tightened the arm is clamped to the bar. One end of the arm I6 is accuracy, and simplicity in- Fig. 2 is a vertical, sectional view taken on relation to a bracket II at their lower ends and.

turned outwardly and tothis is fixed by a bolt l8 one end of an interrupted cylindrical ring l9 comprising a bimetallic thermo-sensitive element. The inner layerof the ring I9 is preferably formed of zinc and the outer layer ofsteel, the 5 two layers. being fastened together throughout their extent as by rivets and solder the arrangement being .such that as the temperature increases the ring attempts to straighten and increases in radius. 10

An annular graduated discis fixed to the arm I6 by screws 2|, 2|" and spacers 22, 22'. An adjustable stop screw 23 is threaded through the cross head l5 so as to rest upon the bimetallic ring l9, and is held in adjustment by a jamb-nut l5- 2 4. An indicating mark 25 is formed on the cross head I5 near the graduated'perimeter of the disc 20. The cross head IE will be raised by increases of temperature and lowered by decreases of temperature and. the amplitude of such 20 movements will be controlled by the relative setting of the arm I 6 with the cross bar I 2 inasmuch as by this setting the efi'ective length of thebimetallic element H! from its point of attachment at [8 to the screw 23 is adjustably determinedmgfi An annular 'plate 26 is supported above'the cross -head I 5 'at a fixed distance therefrom by a pair of rods 21, 21-. A'stud 28 rotatably mounted through a central aperture in plate'26 formed with a threaded portion 29 and an en-.

larged shoulder 30 below the plate and a squared portion 3| above the plate. .An adjusting wheel 32 having a graduated depending rim 33 engages the squared portion of the stud and is held thereon by a nut 34. An index finger 35 fixed to the 35 plate 26 extends in close relation to the graduated rim to indicate its adjustment.

An internally threaded cap 36 engages the threaded end 29 of the stud and is provided with a cross bar 31 which slideably engages the rods 21, 21'. A pair of coil springs 38, 38 of the compression'type encompass the rods 21, 21' and resiliently hold the plate 26 and cross bar 31 in spaced relation. The cap 36 is formed with a depending hook 39 adapted to support the upper end-of a strip 40 of hygroscopic material the lower end of which is attached to a cross head ll slideably mounted on rods I 0, III. The strip 40 may be formed of any suitable material hav-.-

ing the property of changing its length under the influence of moisture. The preferred material is a strip of old heaters skin which contracts when dry and expands when damp.

While the described mechanism may be used to record the combined efiect of moisture and temperature by connecting the cross head M to suitable indicating mechanism, the device may also be used to control the addition of moisture to the atmosphere for the purpose of conditioning the air. For this purpose the cross head ll may be directly connected to the gate 42 of a valve 43 adapted to control the emission 01 air from a pipe 44 to the nozzle 45 of a atomizer, the water being drawn from a suitable vessel ii by suction created by the high velocity of. the air across the suctiontube 41.

In the operation of the device reduction of moisture in the atmosphere causes the strip 50 to shorten and open the valve 43 until such time as the surrounding air is provided with sufflcient moisture to meet the desired requirement whereupon the valve closes. Increase in temperature causes the'strip 40 to be raised by an amount depending upon the position of the dial 20. The

strip llv may also lengthen under the increased temperature, such lengthening being more or less compensated for by the position of the dial It. The movements caused by the changes in temperature and humidity are compounded to produce resulting movement of the valve. A device so constructed wiilprovide' a greater amount of moisture in the atmosphere at elevated temperatures and a lower amount at reduced temperatures than a device responsive merely to' the humidity of the air and is'very desirable for use in conditioning the air in textile mills and other factories where high humidity is desirable.

Thetemperature responsive element I 9 may also be made with the layer having the higher expansibility, such as zinc, on the outside andthe layer of lower expansibility, such as steel on the inside, in which case-the device will providea greater proportion of moisture at reduced temperatures and a lower proportion at elevated temperatures and the device will be useful in conditioning air in dwellings, oilices, theatres, and other buildings Where it may be desired to lessen the relative humidity during hot weather and increase it during cold weather to bring the 59 sponsive to humidity an element movmes es able in the vertical direction in response to temperature changes, a carrying stmcture interposed between said elements and. resting with at least a part of its weight upon the temperature responsive element to follow the vertical movements thereof, said carrying element includtions, said apparatus comprising an element responsive to humidity changes, a temperature responsive strip element mounted at one of its ends for fiexure in increasing vertical increments away from said end under temperature changes, a carrying structure resting with at least a part of its weight upon said strip element to follow the vertical movements thereof, the humidity-responsive element being supported by said carrying structure, means for adjusting the position of said carrying structure along the strip element toward and away from the mounted end of. the

' axis, a carrying structure resting with at least a put of its weight upon the uppermost portion of said strip element'to follow the vertical movements thereof, the humidity responsive element being suspended from said carrying structure and a control element mounted for operation by movement of the humidity responsive element.

ALBERT T. MATTHEWS. CHARLES C. CADDEN. 

